What would you do if you felt your partner had hidden a major part of his/her personality away from you?

I use the term personality lightly. Let’s say for example that for years he was a binge eater and hid it from you. Or she was a kleptomaniac that hid all her trophies in the basement. Perhaps you found a letter to your husband from a sister you never knew existed.Perhaps you stumbled upon your husbands cross dressing kit.

What would you feel? Shock of course? Would you lose trust and end it? Or, if you decided to accept this shocking news, how would you rebuild trust?